Pod::InputObjects

Section: Perl Programmers Reference Guide (3perl)
Updated: 2019-04-20
Page Index

NAME

Pod::InputObjects - objects representing POD input paragraphs, commands, etc.

SYNOPSIS

    use Pod::InputObjects;

REQUIRES

perl5.004, Carp

EXPORTS

Nothing.

DESCRIPTION

NOTE: This module is considered legacy; modern Perl releases (5.18 and higher) are going to remove Pod-Parser from core and use Pod-Simple for all things POD.

This module defines some basic input objects used by Pod::Parser when reading and parsing POD text from an input source. The following objects are defined:

package Pod::Paragraph: An object corresponding to a paragraph of POD input text. It may be a plain paragraph, a verbatim paragraph, or a command paragraph (see perlpod).
package Pod::InteriorSequence: An object corresponding to an interior sequence command from the POD input text (see perlpod).
package Pod::ParseTree: An object corresponding to a tree of parsed POD text. Each ``node'' in a parse-tree (or ptree) is either a text-string or a reference to a Pod::InteriorSequence object. The nodes appear in the parse-tree in the order in which they were parsed from left-to-right.

Each of these input objects are described in further detail in the sections which follow.

Pod::Paragraph

An object representing a paragraph of POD input text. It has the following methods/attributes:

Pod::Paragraph->new()

        my $pod_para1 = Pod::Paragraph->new(-text => $text);
        my $pod_para2 = Pod::Paragraph->new(-name => $cmd,
                                            -text => $text);
        my $pod_para3 = new Pod::Paragraph(-text => $text);
        my $pod_para4 = new Pod::Paragraph(-name => $cmd,
                                           -text => $text);
        my $pod_para5 = Pod::Paragraph->new(-name => $cmd,
                                            -text => $text,
                                            -file => $filename,
                                            -line => $line_number);

This is a class method that constructs a "Pod::Paragraph" object and returns a reference to the new paragraph object. It may be given one or two keyword arguments. The "-text" keyword indicates the corresponding text of the POD paragraph. The "-name" keyword indicates the name of the corresponding POD command, such as "head1" or "item" (it should not contain the "=" prefix); this is needed only if the POD paragraph corresponds to a command paragraph. The "-file" and "-line" keywords indicate the filename and line number corresponding to the beginning of the paragraph

$pod_para->cmd_name()

        my $para_cmd = $pod_para->cmd_name();

If this paragraph is a command paragraph, then this method will return the name of the command (without any leading "=" prefix).

$pod_para->text()

        my $para_text = $pod_para->text();

This method will return the corresponding text of the paragraph.

$pod_para->raw_text()

        my $raw_pod_para = $pod_para->raw_text();

This method will return the raw text of the POD paragraph, exactly as it appeared in the input.

$pod_para->cmd_prefix()

        my $prefix = $pod_para->cmd_prefix();

If this paragraph is a command paragraph, then this method will return the prefix used to denote the command (which should be the string ``='' or ``=='').

$pod_para->cmd_separator()

        my $separator = $pod_para->cmd_separator();

If this paragraph is a command paragraph, then this method will return the text used to separate the command name from the rest of the paragraph (if any).

$pod_para->parse_tree()

        my $ptree = $pod_parser->parse_text( $pod_para->text() );
        $pod_para->parse_tree( $ptree );
        $ptree = $pod_para->parse_tree();

This method will get/set the corresponding parse-tree of the paragraph's text.

$pod_para->file_line()

        my ($filename, $line_number) = $pod_para->file_line();
        my $position = $pod_para->file_line();

Returns the current filename and line number for the paragraph object. If called in a list context, it returns a list of two elements: first the filename, then the line number. If called in a scalar context, it returns a string containing the filename, followed by a colon (':'), followed by the line number.

Pod::InteriorSequence

An object representing a POD interior sequence command. It has the following methods/attributes:

Pod::InteriorSequence->new()

        my $pod_seq1 = Pod::InteriorSequence->new(-name => $cmd
                                                  -ldelim => $delimiter);
        my $pod_seq2 = new Pod::InteriorSequence(-name => $cmd,
                                                 -ldelim => $delimiter);
        my $pod_seq3 = new Pod::InteriorSequence(-name => $cmd,
                                                 -ldelim => $delimiter,
                                                 -file => $filename,
                                                 -line => $line_number);

        my $pod_seq4 = new Pod::InteriorSequence(-name => $cmd, $ptree);
        my $pod_seq5 = new Pod::InteriorSequence($cmd, $ptree);

This is a class method that constructs a "Pod::InteriorSequence" object and returns a reference to the new interior sequence object. It should be given two keyword arguments. The "-ldelim" keyword indicates the corresponding left-delimiter of the interior sequence (e.g. '<'). The "-name" keyword indicates the name of the corresponding interior sequence command, such as "I" or "B" or "C". The "-file" and "-line" keywords indicate the filename and line number corresponding to the beginning of the interior sequence. If the $ptree argument is given, it must be the last argument, and it must be either string, or else an array-ref suitable for passing to Pod::ParseTree::new (or it may be a reference to a Pod::ParseTree object).

$pod_seq->cmd_name()

        my $seq_cmd = $pod_seq->cmd_name();

The name of the interior sequence command.

$pod_seq->prepend()

        $pod_seq->prepend($text);
        $pod_seq1->prepend($pod_seq2);

Prepends the given string or parse-tree or sequence object to the parse-tree of this interior sequence.

$pod_seq->append()

        $pod_seq->append($text);
        $pod_seq1->append($pod_seq2);

Appends the given string or parse-tree or sequence object to the parse-tree of this interior sequence.

$pod_seq->nested()

        $outer_seq = $pod_seq->nested || print "not nested";

If this interior sequence is nested inside of another interior sequence, then the outer/parent sequence that contains it is returned. Otherwise "undef" is returned.

$pod_seq->raw_text()

        my $seq_raw_text = $pod_seq->raw_text();

This method will return the raw text of the POD interior sequence, exactly as it appeared in the input.

$pod_seq->left_delimiter()

        my $ldelim = $pod_seq->left_delimiter();

The leftmost delimiter beginning the argument text to the interior sequence (should be ``<'').

$pod_seq->right_delimiter()

The rightmost delimiter beginning the argument text to the interior sequence (should be ``>'').

$pod_seq->parse_tree()

        my $ptree = $pod_parser->parse_text($paragraph_text);
        $pod_seq->parse_tree( $ptree );
        $ptree = $pod_seq->parse_tree();

This method will get/set the corresponding parse-tree of the interior sequence's text.

$pod_seq->file_line()

        my ($filename, $line_number) = $pod_seq->file_line();
        my $position = $pod_seq->file_line();

Returns the current filename and line number for the interior sequence object. If called in a list context, it returns a list of two elements: first the filename, then the line number. If called in a scalar context, it returns a string containing the filename, followed by a colon (':'), followed by the line number.

Pod::InteriorSequence::DESTROY()

This method performs any necessary cleanup for the interior-sequence. If you override this method then it is imperative that you invoke the parent method from within your own method, otherwise interior-sequence storage will not be reclaimed upon destruction!

Pod::ParseTree

This object corresponds to a tree of parsed POD text. As POD text is scanned from left to right, it is parsed into an ordered list of text-strings and Pod::InteriorSequence objects (in order of appearance). A Pod::ParseTree object corresponds to this list of strings and sequences. Each interior sequence in the parse-tree may itself contain a parse-tree (since interior sequences may be nested).

Pod::ParseTree->new()

        my $ptree1 = Pod::ParseTree->new;
        my $ptree2 = new Pod::ParseTree;
        my $ptree4 = Pod::ParseTree->new($array_ref);
        my $ptree3 = new Pod::ParseTree($array_ref);

This is a class method that constructs a "Pod::Parse_tree" object and returns a reference to the new parse-tree. If a single-argument is given, it must be a reference to an array, and is used to initialize the root (top) of the parse tree.

$ptree->top()

        my $top_node = $ptree->top();
        $ptree->top( $top_node );
        $ptree->top( @children );

This method gets/sets the top node of the parse-tree. If no arguments are given, it returns the topmost node in the tree (the root), which is also a Pod::ParseTree. If it is given a single argument that is a reference, then the reference is assumed to a parse-tree and becomes the new top node. Otherwise, if arguments are given, they are treated as the new list of children for the top node.

$ptree->children()

This method gets/sets the children of the top node in the parse-tree. If no arguments are given, it returns the list (array) of children (each of which should be either a string or a Pod::InteriorSequence. Otherwise, if arguments are given, they are treated as the new list of children for the top node.

$ptree->prepend()

This method prepends the given text or parse-tree to the current parse-tree. If the first item on the parse-tree is text and the argument is also text, then the text is prepended to the first item (not added as a separate string). Otherwise the argument is added as a new string or parse-tree before the current one.

$ptree->append()

This method appends the given text or parse-tree to the current parse-tree. If the last item on the parse-tree is text and the argument is also text, then the text is appended to the last item (not added as a separate string). Otherwise the argument is added as a new string or parse-tree after the current one.

$ptree->raw_text()

        my $ptree_raw_text = $ptree->raw_text();

This method will return the raw text of the POD parse-tree exactly as it appeared in the input.

Pod::ParseTree::DESTROY()

This method performs any necessary cleanup for the parse-tree. If you override this method then it is imperative that you invoke the parent method from within your own method, otherwise parse-tree storage will not be reclaimed upon destruction!

AUTHOR

Please report bugs using <http://rt.cpan.org>.

Brad Appleton <bradapp@enteract.com>